A method for analyzing impurities in solder mask layer of packaging substrate

Abstract

The present invention provides a method for analyzing impurities in a solder mask layer of a packaging substrate, comprising the following steps: obtaining the composition information of the solder mask layer; obtaining the composition information of the impurities, the composition information of the impurities including the composition information on the surface of the impurities and the composition information inside the impurities; obtaining the appearance information of the impurities; obtaining the composition information of suspicious objects on site; based on the comparison and analysis of the composition information of the solder mask layer, the composition information of the impurities, the appearance information of the impurities and the composition information of the suspicious objects on site, inferring the actual source of the impurities. The method for analyzing impurities in a solder mask layer of a packaging substrate provided by the present invention can quickly and accurately infer the actual source of impurities in the solder mask layer by testing and analyzing the internal composition information and the three-dimensional size and distribution of the impurities in the solder mask layer, thereby effectively improving the performance and quality of the packaging substrate and reducing the production defect rate of the packaging substrate.

Description

Technical Field

[0001] The invention belongs to the technical field of manufacturing printed circuit boards or semiconductor integrated circuit packaging substrates, and relates to an analysis method for impurities in a solder mask layer of a packaging substrate. Background Art

[0002] As the entire chip industry is pursuing the trend of low power consumption, high speed, high density and low voltage, the demand for packaging substrates in the chip field is increasing, and the requirements for their performance and quality are also getting higher and higher. In the process of packaging substrate production, solder mask debris is an important factor affecting the performance and quality of packaging substrates, and also greatly affects the yield of packaging substrate production.

[0003] For the conventional analysis method of impurities in package substrates, it is usually a glue-filling method, and the package substrate samples with impurities are subjected to energy dispersive spectroscopy (EDS) analysis and slice analysis. EDS analysis can only judge the elemental composition on the surface of the impurities, and cannot directly analyze the elements inside the sample impurities, and the analysis accuracy of ultra-light elements such as C and O is low. In order to test the elements inside the impurities, it is generally necessary to grind and polish the cross section of the impurities, which will cause secondary contamination of polishing powder or polishing liquid, and will also increase the risk of the impurities disappearing after grinding and polishing. Slice analysis mainly grinds the slice longitudinally until it reaches the place containing impurities, and observes the position of the impurities under an electron microscope, that is, the height difference between the copper thickness under nickel gold and the copper thickness under the impurities, so as to preliminarily judge whether the impurities are generated before or during the solder mask process, that is, the slice analysis can only roughly infer the process of impurity generation, and it is even more impossible to judge the type and source of the impurities. Therefore, the above two conventional analysis methods of basic impurities in package have certain limitations. When the impurities are organic matter, it is difficult to determine their composition to determine their possible sources.

[0004] Based on the above situation, for organic impurities containing ultra-light elements such as C and O, an infrared spectroscopic microscope can be used to analyze the chemical bonds (functional groups) of the impurities, so that its composition and source can be determined more accurately, thereby improving the accuracy and practicality of failure analysis. However, an infrared spectroscopic microscope can only detect the infrared absorption spectrum on the surface of the impurities, that is, it can only determine the surface composition of the impurities, but not the internal composition of the impurities. After the solder resist process, the impurities are likely to be wrapped with a layer of solder resist. If infrared spectroscopy is directly performed, only the composition of the surface solder resist will be detected.

[0005] Therefore, how to provide a method that can analyze the internal composition information of the impurities inside the solder mask of the packaging substrate and obtain the appearance characteristics of the impurities, so as to quickly and accurately infer the source of the impurities in the solder mask by comparing and analyzing the internal composition and appearance information of the impurities inside the solder mask with the composition and appearance information of the suspicious objects on site, has become an important technical problem that needs to be urgently solved by technical personnel in this field.

[0006] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present application and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because they are described in the background technology section of the present application. Summary of the invention

[0007] In view of the shortcomings of the prior art described above, an object of the present invention is to provide a method for analyzing impurities in the solder mask layer of a packaging substrate, which is used to solve the problem that the prior art can only analyze the surface composition information of the impurities in the solder mask layer but cannot analyze its internal composition information and appearance information, thereby failing to quickly and accurately infer the source of the impurities.

[0008] To achieve the above-mentioned object and other related objects, the present invention provides a method for analyzing impurities in a solder mask layer of a packaging substrate, comprising:

[0009] Get the composition information of the solder mask layer;

[0010] Acquiring component information of the sundries, wherein the component information of the sundries includes component information on the surface of the sundries and component information inside the sundries;

[0011] Obtaining appearance information of the sundries;

[0012] Obtain appearance and composition information of suspicious objects at the scene;

[0013] Based on the comparative analysis of the composition information of the solder resist layer, the composition information of the debris, the appearance information of the debris, the appearance information of the suspicious objects at the scene and the composition information of the suspicious objects at the scene, the actual source of the debris is inferred.

[0014] Optionally, the method for analyzing impurities in the solder mask layer of the package substrate comprises the following steps:

[0015] A first sample to be tested is manufactured based on the package substrate to be tested, wherein the first sample to be tested includes a substrate layer, a solder resist layer and debris, wherein the solder resist layer is located on the substrate layer and covers the debris;

[0016] Acquire composition information of the surface of the debris and composition information of the solder resist layer based on the first sample to be tested;

[0017] Comparing the component information of the surface of the debris with the component information of the solder resist layer, and if the matching degree of the component information of the surface of the debris with the component information of the solder resist layer reaches a preset value, it is determined that the surface of the debris is still covered with the solder resist layer;

[0018] Removing at least a portion of the solder resist layer on the surface of the debris to obtain a second sample to be tested;

[0019] Acquiring component information inside the impurities based on the second sample to be tested;

[0020] Obtaining appearance information of the sundries;

[0021] Acquire the suspicious object at the scene based on the appearance information of the sundries, and acquire the appearance information of the suspicious object at the scene;

[0022] Comparing the appearance information of the sundries with the appearance information of the suspicious objects at the scene;

[0023] Obtaining composition information of the suspicious object at the scene;

[0024] Comparing the composition information inside the debris with the composition information of the suspicious object at the scene;

[0025] The actual source of the impurities is inferred based on the comparison result. Optionally, the method for preparing the first sample to be tested includes exposing the impurities in the solder resist layer by bare chip grinding.

[0026] Optionally, the preset value is greater than or equal to 90%.

[0027] Optionally, the method for manufacturing the first sample to be tested based on the package substrate to be tested includes: sampling based on a region of the package substrate to be tested containing the impurities and performing bare chip pre-grinding.

[0028] Optionally, the method for obtaining the composition information of the solder resist layer includes obtaining the infrared spectrum of the solder resist layer through an infrared spectroscopic microscope; the method for obtaining the composition information of the debris includes obtaining the infrared spectrum of the debris through an infrared spectroscopic microscope; the method for obtaining the composition information of the suspicious object at the scene includes obtaining the infrared spectrum of the suspicious object at the scene through an infrared spectroscopic microscope.

[0029] Optionally, the comparing the composition information of the debris surface and the composition information of the solder resist layer comprises comparing the infrared spectrum of the debris surface and the infrared spectrum of the solder resist layer, and the characteristics of the compared infrared spectra comprise at least one of peak position, wave number and peak shape.

[0030] Optionally, the method of acquiring the infrared spectrum by the infrared spectroscopic microscope includes at least one of attenuated total reflection, transmission and reflection.

[0031] Optionally, the method of removing at least a portion of the solder resist layer on the surface of the debris comprises performing confocal ion cutting by a focused ion beam scanning electron microscope dual beam system to expose at least a portion of the debris.

[0032] Optionally, the method for obtaining appearance information of the debris includes analyzing the size and shape of the debris using a three-dimensional reconstruction function of a dual-beam system of a focused ion beam scanning electron microscope.

[0033] Optionally, obtaining the appearance information of the sundries comprises the following steps:

[0034] Finding the area to be analyzed in the second sample to be tested and performing focused ion beam cutting to remove obstructions around the area to be analyzed;

[0035] Acquire a cut surface image of the debris and a three-dimensional acquisition image of the spectrometer based on the area to be analyzed;

[0036] A three-dimensional image of the debris is generated based on the cut surface image of the debris and the three-dimensional acquisition image of the spectrometer to obtain the three-dimensional size and distribution of the debris.

[0037] A first sample to be tested is manufactured based on the package substrate to be tested, wherein the first sample to be tested includes a substrate layer, a solder resist layer and debris, wherein the solder resist layer is located on the substrate layer and covers the debris;

[0038] Optionally, the method for analyzing impurities in the solder mask layer of the package substrate comprises the following steps:

[0039] Acquire composition information of the surface of the debris and composition information of the solder resist layer based on the first sample to be tested;

[0040] Comparing the component information of the surface of the debris with the component information of the solder resist layer, and if the matching degree between the component information of the surface of the debris and the component information of the solder resist layer does not reach a preset value, determining that the surface of the debris is no longer covered with the solder resist layer;

[0041] Obtaining appearance information of the sundries;

[0042] Acquire the suspicious object at the scene based on the appearance information of the sundries, and acquire the appearance information of the suspicious object at the scene;

[0043] Comparing the appearance information of the sundries with the appearance information of the suspicious objects at the scene;

[0044] Obtaining composition information of the suspicious object at the scene;

[0045] Comparing the composition information inside the debris with the composition information of the suspicious object at the scene;

[0046] The actual source of the impurities is inferred based on the comparison results.

[0047] As described above, the analysis method of impurities in the solder mask layer of a packaging substrate of the present invention comprises the following steps: obtaining the composition information of the solder mask layer; obtaining the composition information of the impurities, the composition information of the impurities including the composition information on the surface of the impurities and the composition information inside the impurities; obtaining the appearance information of the impurities; obtaining the appearance information and composition information of suspicious objects on site; performing comparison and analysis based on the composition information of the solder mask layer, the composition information of the impurities, the appearance information of the impurities, the appearance information of the suspicious objects on site and the composition information of the suspicious objects on site, and inferring the actual source of the impurities. The analysis method of impurities in the solder mask layer of a packaging substrate provided by the present invention can infer the actual source of impurities in the solder mask layer by testing and analyzing the internal composition information and the three-dimensional size and distribution of the impurities in the solder mask layer, thereby effectively improving the performance and quality of the packaging substrate and reducing the production defect rate of the packaging substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic flow chart showing the method for analyzing foreign matters in the solder resist layer of a package substrate of the present invention.

[0049] Figure 2 It is a flow chart showing the steps of the method for analyzing foreign matters in the solder resist layer of a package substrate of the present invention in the first embodiment.

[0050] Figure 3 It is a flow chart showing the steps of the method for analyzing foreign matters in the solder resist layer of a package substrate of the present invention in the second embodiment. DETAILED DESCRIPTION

[0051] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0052] See also Figures 1 to 3 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0053] Embodiment 1

[0054] See also Figure 1, which is a schematic flow chart of a method for analyzing impurities in a solder mask layer of a package substrate of the present invention, comprising the following steps:

[0055] Get the composition information of the solder mask layer;

[0056] Acquiring component information of the sundries, wherein the component information of the sundries includes component information on the surface of the sundries and component information inside the sundries;

[0057] Obtaining appearance information of the sundries;

[0058] Obtain appearance and composition information of suspicious objects at the scene;

[0059] Based on the comparison and analysis of the composition information of the solder resist layer, the composition information of the debris, the appearance information of the debris, the appearance information of the suspicious objects at the scene and the composition information of the suspicious objects at the scene, the actual source of the debris is inferred.

[0060] As an example, see Figure 2 , which is a flowchart of the method for analyzing impurities in the solder mask layer of the package substrate in this embodiment, includes the following steps:

[0061] A first sample to be tested is manufactured based on the package substrate to be tested, wherein the first sample to be tested includes a substrate layer, a solder resist layer and debris, wherein the solder resist layer is located on the substrate layer and covers the debris;

[0062] Acquire composition information of the surface of the debris and composition information of the solder resist layer based on the first sample to be tested;

[0063] Comparing the component information of the surface of the debris with the component information of the solder resist layer, and if the matching degree of the component information of the surface of the debris with the component information of the solder resist layer reaches a preset value, it is determined that the surface of the debris is still covered with the solder resist layer;

[0064] Removing at least a portion of the solder resist layer on the surface of the debris to obtain a second sample to be tested;

[0065] Acquiring component information inside the impurities based on the second sample to be tested;

[0066] Obtaining appearance information of the sundries;

[0067] Acquire the suspicious object at the scene based on the appearance information of the sundries, and acquire the appearance information of the suspicious object at the scene;

[0068] Comparing the appearance information of the sundries with the appearance information of the suspicious objects at the scene;

[0069] Obtaining composition information of the suspicious object at the scene;

[0070] Comparing the composition information inside the debris with the composition information of the suspicious object at the scene;

[0071] The actual source of the impurities is inferred based on the comparison results.

[0072] As an example, when the preset value is greater than or equal to 90%, that is, when the matching degree of the composition information on the surface of the debris and the composition information on the solder resist layer reaches 90%, it can be judged that the surface of the debris is still covered with the solder resist layer. At this time, at least a portion of the solder resist layer on the surface of the debris needs to be removed to obtain the internal composition information of the debris.

[0073] As an example, the method for making the first sample to be tested based on the package substrate to be tested includes: sampling based on the area of ​​the package substrate to be tested containing the impurities and performing bare chip pre-grinding. The purpose of bare chip pre-grinding is to observe the impurities with the naked eye so as to determine the basic position of the impurities to facilitate the next step.

[0074] As an example, the method for obtaining the composition information of the solder resist layer includes obtaining the infrared spectrum of the solder resist layer through an infrared spectroscopic microscope; the method for obtaining the composition information of the impurities includes obtaining the infrared spectrum of the impurities through an infrared spectroscopic microscope; the method for obtaining the composition information of the suspicious objects on site includes obtaining the infrared spectrum of the suspicious objects on site through an infrared spectroscopic microscope. The reason for using infrared spectroscopy to test and analyze the composition information is that infrared spectroscopic microscopes are suitable for detecting trace samples below 1 mm, with a minimum spatial resolution of 1.25 μm, and can complete large-area infrared imaging in a very short time, so it is possible to achieve composition testing of tiny impurities contained in the solder resist layer.

[0075] As an example, the comparing the composition information of the debris surface and the composition information of the solder resist layer includes comparing the infrared spectrum of the debris surface and the infrared spectrum of the solder resist layer, and the characteristics of the compared infrared spectra include at least one of peak position, wave number and peak shape.

[0076] As an example, the method of acquiring the infrared spectrum through the infrared spectroscopic microscope includes using at least one of attenuated total reflectance (Attenuated Total Reflectance, ATR), transmission (Transmitted Reflectance, TR) or reflection (Reflectance, Ref).

[0077] Specifically, obtaining an infrared spectrum through an infrared spectroscopic microscope includes the following steps: placing and fixing the first sample to be tested on the sample stage of the infrared spectroscopic microscope, finding the debris in the first sample to be tested, and measuring the surface of the debris in the first sample to be tested by at least one of attenuated total reflection, transmission or reflection to obtain an infrared spectrum of the surface of the debris in the first sample to be tested. In this embodiment, an array detector can also be used for imaging to obtain the size and distribution of different components on the surface of the debris in the first sample to be tested. Then, the infrared test spectrum of the solder mask in the first sample to be tested is obtained according to the above steps.

[0078] Then compare the infrared spectrum of the surface of the debris with the infrared spectrum of the solder resist layer. If the infrared spectrum of the surface of the debris and the infrared spectrum of the solder resist layer have the same peak position, wave number, peak shape and other characteristics, and the infrared spectrum of the surface of the debris and the infrared spectrum of the solder resist layer match more than 90%, it can be preliminarily determined that the substance on the surface of the debris and the solder resist layer are the same substance, that is, the surface of the debris is still covered with the solder resist layer. At this time, if you want to obtain the composition information inside the debris, you need to remove at least a part of the solder resist layer on the surface of the debris for a deeper level of testing and analysis. In this embodiment, the infrared spectrum of the surface of the debris and the infrared spectrum of the solder resist layer match 90%, that is, the surface of the debris is still covered with the solder resist layer, so at least a part of the solder resist layer on the surface of the debris must be removed to obtain the composition information inside the debris.

[0079] As an example, the method for removing at least a portion of the solder resist layer on the surface of the debris includes performing confocal ion beam (FIB) cutting through a focused ion beam scanning electron microscope (FIB-SEM) dual beam system to reveal at least a portion of the debris.

[0080] As an example, the method of removing at least a portion of the solder resist layer on the surface of the debris includes performing confocal ion cutting by a focused ion beam scanning electron microscope dual beam system to reveal at least a portion of the debris.

[0081] Specifically, the method for removing at least a portion of the solder resist layer on the surface of the debris comprises the following steps: sampling, numbering, pre-judging and marking the position, spraying gold and other pre-treatments on the first sample to be tested to ensure that the first sample to be tested is easy to locate and has good conductivity; fixing the first sample to be tested that has completed the pre-treatment on a sample stage with an inclination angle of 54° with conductive tape, and then placing it in the sample chamber for vacuuming; when the vacuum degree is less than a certain value, turning on the electron beam, adjusting the position of the sample stage, adjusting the test area of ​​the first sample to be tested to just below the electron beam pole shoe, adjusting the Z-axis working distance to the confocal position, and adjusting the electron beam voltage, current, Observe the parameters such as mode, probe, focal length, astigmatism, contrast, brightness, etc.; rotate the 54° pre-tilted sample stage to a certain angle to ensure that the ion beam is level with the surface of the first sample to be tested, find the position on the first sample to be tested that needs to be cut, turn on the ion beam, adjust the ion beam voltage, current, observation mode, probe, focal length, astigmatism, contrast, brightness, etc.; find the cutting position, set the deposition parameters, and perform carbon deposition or tungsten deposition at the cutting position; select the cutting or processing area, set the cutting parameters, perform rough cutting first, and then perform fine trimming, and finally remove at least a portion of the solder resist layer on the surface of the debris to obtain the second sample to be tested.

[0082] After removing at least a portion of the solder resist layer on the surface of the debris, the portion of the debris from which the solder resist layer is removed is measured by an infrared spectroscopic microscope using attenuated total reflection, transmission or reflection to obtain an infrared test spectrum of the debris, thereby obtaining component information inside the debris.

[0083] As an example, the method for obtaining the appearance information of the debris includes analyzing the size and shape of the debris using the three-dimensional reconstruction function of a focused ion beam scanning electron microscope dual beam system. The focused ion beam scanning electron microscope dual beam system can collect a variety of three-dimensional information with high quality and fully automatic.

[0084] As an example, the method of obtaining the appearance information of the debris includes the following steps: finding the area to be analyzed in the second sample to be tested and performing focused ion beam cutting to remove obstructions around the area to be analyzed; obtaining a cutting surface image of the debris and a three-dimensional acquisition image of the spectrometer based on the area to be analyzed; generating a three-dimensional map of the debris based on the cutting surface image of the debris and the three-dimensional acquisition image of the spectrometer to obtain the three-dimensional size and distribution of the debris.

[0085] Specifically, the steps of obtaining the appearance information of the debris are as follows: spray gold on the second sample to be tested to ensure that it has good conductivity; use conductive tape to fix the second sample to be tested that has completed the pretreatment on a sample stage with an inclination angle of 54°, and then put it into the sample chamber for vacuuming; when the vacuum degree is less than a certain value, turn on the electron beam, adjust the position of the sample stage, adjust the test area of ​​the second sample to be tested to just below the electron beam pole shoe, adjust the Z-axis working distance to the confocal position, and adjust the electron beam voltage, current, observation mode, probe, focal length, astigmatism, contrast, brightness and other parameters; rotate the 54° pre-tilted sample stage to a certain angle to ensure that the ion beam is aligned with the second sample to be tested. The surfaces of the two samples to be tested are perpendicular, the area to be analyzed is found, the ion beam is turned on, and the parameters such as ion beam voltage, current, observation mode, probe, focal length, astigmatism, contrast, brightness, etc. are adjusted; deposition parameters are set at the edges of the area to be analyzed, carbon deposition or tungsten deposition is performed at the cutting position, and then confocal ion beam cutting is performed to remove the obstructions around the area to be tested; the three-dimensional reconstruction software of the confocal ion beam scanning electron microscope dual beam system is turned on, and parameters such as the size of the processing area, positioning and cutting method are set; then parameters such as each cutting profile image acquisition and spectrometer acquisition are set; after the operation is completed, the three-dimensional image of the debris and the three-dimensional acquisition image of the spectrometer can be obtained. Then, the three-dimensional reconstruction software of the confocal ion beam scanning electron microscope dual beam system is used to reconstruct the three-dimensional image of the debris and the three-dimensional acquisition image of the spectrometer that have been collected to generate a three-dimensional map of the debris. The three-dimensional size and distribution of the debris can be analyzed from the obtained three-dimensional map of the debris.

[0086] According to the three-dimensional size and distribution of the debris obtained from the above test, suspicious objects of similar size and shape are searched and sampled at the production site, and infrared spectra of the suspicious objects are obtained through an infrared spectroscopic microscope. Then, the infrared spectra inside the debris are compared with the infrared spectra of the suspicious objects. If at least one of the peak position, wave number, peak shape and other characteristics of the infrared spectra of the two are consistent, and the matching degree of the infrared spectra of the two is more than 90%, it can be determined that the debris and the suspicious objects at the scene are the same substance, so that the actual source of the debris can be inferred according to the location of the suspicious objects at the scene.

[0087] Embodiment 2

[0088] The present embodiment provides a method for analyzing impurities in a solder resist layer of a packaging substrate, which is different from the first embodiment in that, in the first embodiment, the matching degree of the composition information on the surface of the impurities and the composition information on the solder resist layer reaches a preset value, and it is necessary to remove at least a portion of the solder resist layer on the surface of the impurities to obtain the composition information inside the impurities, while in the present embodiment, the matching degree of the composition information on the surface of the impurities and the composition information on the solder resist layer does not reach the preset value. At this time, the composition information on the surface of the impurities is the composition information inside the impurities, and the next step can be performed without removing at least a portion of the solder resist layer on the surface of the impurities.

[0089] See also Figure 3 , which is a flowchart of the method for analyzing impurities in the solder mask layer of the package substrate in this embodiment, includes the following steps:

[0090] A first sample to be tested is manufactured based on the package substrate to be tested, wherein the first sample to be tested includes a substrate layer, a solder resist layer and debris, wherein the solder resist layer is located on the substrate layer and covers the debris;

[0091] Acquire composition information of the surface of the debris and composition information of the solder resist layer based on the first sample to be tested;

[0092] Comparing the component information of the surface of the debris with the component information of the solder resist layer, and if the matching degree between the component information of the surface of the debris and the component information of the solder resist layer does not reach a preset value, determining that the surface of the debris is no longer covered with the solder resist layer;

[0093] Obtaining appearance information of the sundries;

[0094] Acquire the suspicious object at the scene based on the appearance information of the sundries, and acquire the appearance information of the suspicious object at the scene;

[0095] Comparing the appearance information of the sundries with the appearance information of the suspicious objects at the scene;

[0096] Obtaining composition information of the suspicious object at the scene;

[0097] Comparing the composition information inside the debris with the composition information of the suspicious object at the scene;

[0098] The actual source of the impurities is inferred based on the comparison results.

[0099] As an example, the preset value is greater than or equal to 90%. In this embodiment, the matching degree of the composition information on the surface of the debris and the composition information on the solder resist layer does not reach 90%, which means that the surface of the debris is no longer covered with the solder resist layer. At this time, the composition information on the surface of the debris is the composition information inside the debris. It is not necessary to remove at least a part of the solder resist layer on the surface of the debris to obtain the composition information inside the debris. The appearance information of the debris can be directly obtained for the first sample to be tested. At this time, the first sample to be tested does not need to be processed and can be directly used as the second sample to be tested in the next step.

[0100] In summary, the analysis method of impurities in the solder mask layer of the packaging substrate of the present invention comprises the following steps: obtaining the composition information of the solder mask layer; obtaining the composition information of the impurities, the composition information of the impurities including the composition information on the surface of the impurities and the composition information inside the impurities; obtaining the appearance information of the impurities; obtaining the appearance information and composition information of the suspicious objects on the scene; based on the composition information of the solder mask layer, the composition information of the impurities, the appearance information of the impurities, the appearance information of the suspicious objects on the scene and the composition information of the suspicious objects on the scene, the actual source of the impurities is inferred. The analysis method of impurities in the solder mask layer of the packaging substrate provided by the present invention can infer the actual source of the impurities in the solder mask layer by testing and analyzing the internal composition information and the three-dimensional size and distribution of the impurities in the solder mask layer, thereby effectively improving the performance and quality of the packaging substrate and reducing the production defect rate of the packaging substrate. Therefore, the present invention effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.

[0101] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for analyzing impurities in a solder mask layer of a package substrate, characterized in that: The following steps are involved: Get the composition information of the solder mask layer; Acquiring component information of the sundries, wherein the component information of the sundries includes component information on the surface of the sundries and component information inside the sundries; Obtaining appearance information of the sundries; Obtain appearance and composition information of suspicious objects at the scene; Based on the composition information of the solder mask layer, the composition information of the debris, the appearance information of the debris, the appearance information of the suspicious object at the scene and the composition information of the suspicious object at the scene, a comparison analysis is performed to infer the actual source of the debris; A first sample to be tested is manufactured based on the package substrate to be tested, wherein the first sample to be tested includes a substrate layer, a solder resist layer and debris, wherein the solder resist layer is located on the substrate layer and covers the debris; Acquire composition information of the surface of the debris and composition information of the solder resist layer based on the first sample to be tested; Comparing the component information of the surface of the debris with the component information of the solder resist layer, and if the matching degree of the component information of the surface of the debris with the component information of the solder resist layer reaches a preset value, it is determined that the surface of the debris is still covered with the solder resist layer; Removing at least a portion of the solder resist layer on the surface of the debris to obtain a second sample to be tested; Acquiring component information inside the impurities based on the second sample to be tested; Obtaining appearance information of the sundries; Acquire the suspicious object at the scene based on the appearance information of the sundries, and acquire the appearance information of the suspicious object at the scene; Comparing the appearance information of the sundries with the appearance information of the suspicious objects at the scene; Obtaining composition information of the suspicious object at the scene; Comparing the composition information inside the debris with the composition information of the suspicious object at the scene; The actual source of the impurities is inferred based on the comparison results.

2. The method for analyzing impurities in the solder mask layer of a package substrate according to claim 1, characterized in that: The preset value is greater than or equal to 90%.

3. The method for analyzing impurities in the solder mask layer of a package substrate according to claim 1, characterized in that: The method for obtaining the composition information of the solder resist layer includes obtaining the infrared spectrum of the solder resist layer through an infrared spectrum microscope; the method for obtaining the composition information of the debris includes obtaining the infrared spectrum of the debris through an infrared spectrum microscope; the method for obtaining the composition information of the suspicious object at the scene includes obtaining the infrared spectrum of the suspicious object at the scene through an infrared spectrum microscope.

4. The method for analyzing impurities in the solder mask layer of a package substrate according to claim 3, characterized in that: The comparing the component information of the debris surface and the component information of the solder resist layer comprises comparing the infrared spectrum of the debris surface and the infrared spectrum of the solder resist layer, and the characteristics of the compared infrared spectrum comprise at least one of peak position, wave number and peak shape.

5. The method for analyzing impurities in the solder mask layer of a package substrate according to claim 3, characterized in that: The method of obtaining infrared spectrum by the infrared spectroscopic microscope includes at least one of attenuated total reflection, transmission and reflection.

6. The method for analyzing impurities in the solder mask layer of a package substrate according to claim 1, characterized in that: The method for removing at least a portion of the solder resist layer on the surface of the debris comprises performing confocal ion cutting by a focused ion beam scanning electron microscope dual beam system to reveal at least a portion of the debris.

7. The method for analyzing impurities in the solder mask layer of a package substrate according to claim 1, characterized in that: The method for obtaining appearance information of the debris includes analyzing the size and shape of the debris using a three-dimensional reconstruction function of a dual-beam system of a focused ion beam scanning electron microscope.

8. The method for analyzing impurities in the solder mask layer of a package substrate according to claim 1, characterized in that: The obtaining of the appearance information of the sundries comprises the following steps: Finding the area to be analyzed in the second sample to be tested and performing focused ion beam cutting to remove obstructions around the area to be analyzed; Acquire a cut surface image of the debris and a three-dimensional acquisition image of the spectrometer based on the area to be analyzed; A three-dimensional image of the debris is generated based on the cut surface image of the debris and the three-dimensional acquisition image of the spectrometer to obtain the three-dimensional size and distribution of the debris.

9. The method for analyzing impurities in the solder mask layer of a package substrate according to claim 1, characterized in that: The following steps are involved: A first sample to be tested is manufactured based on the package substrate to be tested, wherein the first sample to be tested includes a substrate layer, a solder resist layer and debris, wherein the solder resist layer is located on the substrate layer and covers the debris; Acquire composition information of the surface of the debris and composition information of the solder resist layer based on the first sample to be tested; Comparing the component information of the surface of the debris with the component information of the solder resist layer, and if the matching degree between the component information of the surface of the debris and the component information of the solder resist layer does not reach a preset value, determining that the surface of the debris is no longer covered with the solder resist layer; Obtaining appearance information of the sundries; Acquire the suspicious object at the scene based on the appearance information of the sundries, and acquire the appearance information of the suspicious object at the scene; Comparing the appearance information of the sundries with the appearance information of the suspicious objects at the scene; Obtaining composition information of the suspicious object at the scene; Comparing the composition information inside the debris with the composition information of the suspicious object at the scene; The actual source of the impurities is inferred based on the comparison results.

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